Integral 1 to 2 of (x^3)lnxdx

What do we use as u? I tried lnx and x^3 and it didnt seem to work.

Printable View

- Mar 4th 2013, 02:53 PMSteelers72Definite integral with u substitution
Integral 1 to 2 of (x^3)lnxdx

What do we use as u? I tried lnx and x^3 and it didnt seem to work. - Mar 4th 2013, 03:39 PMBobPRe: Definite integral with u substitution
The method is to integrate by parts.

- Mar 4th 2013, 06:26 PMhollywoodRe: Definite integral with u substitution
You should remember the acronym LIATE: you want to choose for u whatever comes first in the list Logarithmic, Inverse trigonometric, Algebraic, Trigonometric, Exponential. In this case you would choose .

- Hollywood - Mar 4th 2013, 09:49 PMSteelers72Re: Definite integral with u substitution
- Mar 5th 2013, 12:36 AMsbhatnagarRe: Definite integral with u substitution
Here's another method:

Differentiate with respect to :

Putting , gives the answer